The biggest thing I worry about it wind insomuch as how it will affect getting the boat out. I catch very few fish sitting at the mooring in 30 knt wind. I find I have my best fishing on full moon tides but you never know when a huge cow is going to hit.
i'd say darkness. i go when i can, but try to look ahead at the forecast, moon phase, moon rise and set times, etc. and try to focus my efforts on the darkest nights/times i can get out.
"Remember, my friend, that knowledge is stronger than memory, and we should not trust the weaker" - Van Helsing